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Complexos metálicos luminescentes com ácidos fenólicos coordenados: alvos seletivos a mitocôndrias e mapeamento da atividade antioxidante in vitro e in vivo por técnicas fluorescentes
(Universidade Federal de São Carlos, 2017-11-16) Silva, Eldevan Santos; Carlos, Rose Maria; https://lattes.cnpq.br/1589143355309943; https://lattes.cnpq.br/3658375577541136
In this work, the syntheses and characterizations of the complexes are presented, cis-[Mg(phen)(iso)(H2O)3](CH3COO) and [Mg(RPA)(iso)(H2O)(OH)], where phn =phenanthroline, iso= isovanillic , and N-(9-(2-(((4-((1,10-phenanthrolin-5-yl)carbamoyl)benzyl)oxy)carbonyl)phenyl)-6-ethylamino) -3H-xanthen-3-ylidene)-N-ethylethanaminium bromide (RPA) by elemental analysis of C, H, N and thermogravimetric analysis and by NMR of 1H and 13C, 2D COSY and DOSY. Compared to isovanillic acid, the complexes obtained are stable in the solid state, in aqueous solution and are not photodegradable. The insecticidal activity of cis-[Mg(phen)(iso)(H2O)3](CH3COO) in the form of the baits (2.0mgg-1) investigated against leaf-cutting ants of the genus Atta sexdens rubropilosa presented a mode of action slow with 100% mortality on the sixth day, S50 = 2b, and complete inhibition of the development of the symbiotic fungus leucoagaricus gongylophorus. This complex did not show any toxicity to aquatic environment when exposed to paulistinha fish (Zebrafish) for 96 hours at a concentration of 2.0 mgL-1. It also showed no toxicity in the terrestrial environment. In this chronic study during 21day, male Wistar rats were treated with cis-[Mg(phen)(iso)(H2O)3](CH3COO) complex saline solution via intraperitoneal (3.0 mg/kg). Behavioral studies (open field, forced swimming and high cross labyrinth) have suggested that this complex possesses characteristics of anxiolytic drugs. Complex I has high inhibition capacity to oxygen reactive species (1O2, O2•‾), with IC50 below 100M. It has presented excellent inhibition of lipid peroxidation (ROO•, LO•) investigated in pork samples with IC50 at the scale 500 mmolL-1. complex, presented in this work, opens a new horizon of applications in agricultural, medic, and food areas.
Estudo do método de mistura das suspensões precipitadas (MPS) para a síntese de catalisadores de tungstênio suportado em zircônia (WOx/ZrO2)
(Universidade Federal de São Carlos, 2017-11-16) Piva, Diógenes Honorato; Urquieta-González, Ernesto Antonio; https://lattes.cnpq.br/2389975677904655; Morelli, Márcio Raymundo; https://lattes.cnpq.br/0172837599844991; https://lattes.cnpq.br/7567907196509661
Zirconia-supported tungsten oxide (WOx/ZrO2) is one of the main acid catalysts. The development of new methods for its preparation has been widely studied lately. This thesis presents a study of a new synthesis method, named Mixed Precipited Suspension (MPS), to prepare WOx/ZrO2 catalysts. This method consists in the mix of the precipitated suspensions containing the elements of interest, appropriate homogeneity during the mixing step and activation by heat treatment. The dependence of the catalyst properties were investigated as function of synthesis conditions (time and temperature during the mixing step), tungsten content and calcination temperature. The catalysts were characterized and their activity evaluated for oxidative desulfurization (ODS) of model fuel containing dibenzothiophene (DBT). Results show that high mixing time of the suspensions increase the tetragonal ZrO2 phase concentration and the surface area of the catalysts. Furthermore, an improvement of the activity is observed in the catalysts obtained after larger mixing time, which was attributed to the high dispersed distorted Zr-WOx clusters, polytungstate species and no formation of crystalline WO3. The presence of tungstite and the increase of the temperature during the mixing step are prejudicial to achieve highly active catalysts. In addition, the increase in the WOx surface density to values above the monolayer surface coverage (4.5 W nm-2) aid the formation of active species and, consequently, catalysts more effective. Moreover, MPS method manteined the nominal composition and prepared catalysts with higher activity than those obtained by impregnation, for all calcination temperature studied. These results demonstrate the potentiality of MPS method for preparing WOx/ZrO2 catalysts.